Thread by @we_vent

1/Lesson #5: Pressure Regulated Volume Control (PRVC)

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Resource: bit.ly/2MImYv3 by @emireles_c et al

2/ PRVC = Continuous Mandatory Ventilation, Pressure Limited, Time Cycled with Adaptive Targeting.

SETTINGS: Tidal volume, Insp Time, Fio2, PEEP, RR

Breath to Breath feedback of exhaled TV, compared to target with adjustment of subsequent insp pressure to lead to steady TV

3/ ALSO KNOWN AS #AKA...

PRVC - Marquet Servo i
Autoflow - Drager
Adaptive Pressure Ventilation - Hamilton Galileo
Volume Control + - Puritan Bennett
Volume Targeted Pressure Control, Pressure Controlled Volume Guaranteed - Engstrom

4/ Resultant tidal volume dependent on lung compliance and resistance, as well as patient effort.
More patient effort, with subsequent reduction in inspiratory pressure to achieve steady TV

5/
Maintains average minimal tidal volume despite improving or worsening lung mechanics (compliance or resistance)

In the case 👇👇, worsening compliance

6/ Important notes:
1) NOT a volume controlled mode. Only ensures average minimal TV
2) With steady insp pressure, flow rates as demanded by patient = more comfortable
3) Automatically reduces ventilatory support with improved patient effort (ie. waking up from #anesthesia

7/ IMPORTANT, not good mode for patient with severe metabolic acidosis with compensatory increased respiratory drive!!
"Inspiratory pressure will decreased to maintain the targeted average TV, inappropriately shifting the work of breathing onto the patient"